It´s usual to replace the pilot chute or reline the canopy with 323 jumps?

Blue skies.

Pilot chutes are life-limited items, depending on the materials used, it could be due for a replacement, it is also quite possible that the kill line is no longer allowing it to fully cock itself.

Line sets usually take longer to need replacement, but depending on the length of the brake lines, you could start having different openings. Usually the brake lines are due for a replacement before the rest of the line set.

Could you explain the mechanism by which that would slow down the openings?

No, I can't. I haven't quite figured out why. But I know that canopies which will still flair and land well but open very slowly have high permeability on the bottom skin. I have seen this on a variety of canopies both ZP & F-111. The canopy in question has very few jumps so it colud have been just a bad batch or color, all of which I have seen.

Interesting. Canopies open by inflation through the nose don't they? If the bottom skin is porous could it be possible that air flowing into the nose has to fight with air being forced through the bottom skin before the canopy inflates?

It´s usual to replace the pilot chute or reline the canopy with 323 jumps?

Blue skies.

Your packing technique can wear a pilot chute out faster. I know of a jumper that destroyed one in about 150 jumps. The way she was packing it the bridle was rubbing across it bad and just wore it out. Put a bunch holes in it.